diff --git a/extra/PureConor.lagda b/extra/PureConor.lagda
new file mode 100644
index 00000000..73404f57
--- /dev/null
+++ b/extra/PureConor.lagda
@@ -0,0 +1,208 @@
+---
+title     : "Pure: Pure Type Systems"
+layout    : page
+permalink : /Pure/
+---
+
+Barendregt, H. (1991). Introduction to generalized type
+systems. Journal of Functional Programming, 1(2),
+125-154. doi:10.1017/S0956796800020025
+
+Attempt to create inherently typed terms with Connor.
+
+
+## Imports
+
+\begin{code}
+module PureConor where
+\end{code}
+
+\begin{code}
+import Relation.Binary.PropositionalEquality as Eq
+open Eq using (_≡_; refl; sym; trans; cong)
+open import Data.Empty using (⊥; ⊥-elim)
+open import Data.Nat using (ℕ; zero; suc; _+_; _∸_)
+open import Data.Product using (_×_; Σ; Σ-syntax; proj₁; proj₂)
+  renaming (_,_ to ⟨_,_⟩)
+open import Data.Unit using (⊤; tt)
+open import Data.Sum using (_⊎_; inj₁; inj₂)
+open import Function using (_∘_)
+open import Function.Equivalence using (_⇔_; equivalence)
+open import Relation.Nullary using (¬_; Dec; yes; no)
+open import Relation.Nullary.Decidable using (map)
+open import Relation.Nullary.Negation using (contraposition)
+open import Relation.Nullary.Product using (_×-dec_)
+\end{code}
+
+## Syntax
+
+\begin{code}
+infix   4  _⊢_
+infix   4  _∋_
+infix   4  _⊆_
+infixl  5  _,_
+infix   6  _/_
+infix   6  ƛ_⇒_
+infix   7  Π_⇒_
+-- infixr  8  _⇒_
+infixl  9  _·_
+
+data Sort : Set where
+  * : Sort
+  ▢ : Sort
+
+ok2 : Sort → Sort → Set
+ok2 * ▢  =  ⊤
+ok2 _ _  =  ⊥
+
+ok3 : Sort → Sort → Sort → Set
+ok3 * * ▢  =  ⊤
+ok3 * ▢ ▢  =  ⊤
+ok3 ▢ * *  =  ⊤
+ok3 ▢ ▢ ▢  =  ⊤
+ok3 _ _ _  =  ⊥
+
+data Ctx : Set
+
+data Tp : ∀ (Γ : Ctx) → Set
+data _∋_ : ∀ (Γ : Ctx) → Tp Γ → Set
+data _⊢_ : ∀ (Γ : Ctx) → Tp Γ → Set
+
+data _⟶_ {Γ : Ctx} {A : Tp Γ} : Γ ⊢ A → Γ ⊢ A → Set
+data _=β_ {Γ : Ctx} {A : Tp Γ} : Γ ⊢ A → Γ ⊢ A → Set
+
+data Ctx where
+
+  ∅ :
+      ---
+      Ctx
+
+  _,_ : 
+      (Γ : Ctx)
+    → (A : Tp Γ)
+      -----------
+    → Ctx
+
+data Tp where
+
+  ⟪_⟫ : ∀ {Γ : Ctx}
+    → Sort
+      ----
+    → Tp Γ
+
+  ⌈_⌉ : ∀ {Γ : Ctx} {s : Sort}
+    → Γ ⊢ ⟪ s ⟫
+      ----------
+    → Tp Γ
+
+  W : ∀ {Γ : Ctx} {A : Tp Γ}
+    → Tp Γ
+      -----------
+    → Tp (Γ , A)
+
+-- vcons : Π (n : ℕ) → Vec n → Vec (suc n)
+
+_[_] : ∀ {Γ : Ctx}
+  → {A : Tp Γ}
+  → (B : Tp (Γ , A))
+  → (M : Γ ⊢ A)
+    ----------------
+  → Tp Γ
+
+_⟨_⟩ : ∀ {Γ : Ctx} {A : Tp Γ} {B : Tp (Γ , A)}
+  → (N : Γ , A ⊢ B)
+  → (M : Γ ⊢ A)
+    ---------------
+  → Γ ⊢ B [ M ]
+
+data _∋_ where
+
+  Z : ∀ {Γ : Ctx} {A : Tp Γ}
+      ----------------------
+    → Γ , A ∋ W A
+
+  S : ∀ {Γ : Ctx} {A B : Tp Γ}
+    → Γ ∋ B
+      -----------
+    → Γ , A ∋ W B
+
+data _⊢_ where
+
+  ⟪_⟫ : ∀ {Γ : Ctx} {t : Sort}
+    → (s : Sort)
+    → {_ : ok2 s t}
+      -------------
+    → Γ ⊢ ⟪ t ⟫
+
+  ⌊_⌋ : ∀ {Γ : Ctx} {A : Tp Γ}
+    → Γ ∋ A
+      -----
+    → Γ ⊢ A
+
+  Π_⇒_ : ∀ {Γ : Ctx} {s t u : Sort} {stu : ok3 s t u} 
+    → (A : Γ ⊢ ⟪ s ⟫)
+    → Γ , ⌈ A ⌉ ⊢ ⟪ t ⟫
+      ------------------
+    → Γ ⊢ ⟪ u ⟫
+
+  ƛ_⇒_ : ∀ {Γ : Ctx} {s t u : Sort} {stu : ok3 s t u}
+    → (A : Γ ⊢ ⟪ s ⟫)
+    → {B : Γ , ⌈ A ⌉ ⊢ ⟪ t ⟫}
+    → Γ , ⌈ A ⌉ ⊢ ⌈ B ⌉
+      -------------------------------------
+    → Γ ⊢ ⌈ Π_⇒_ {u = u} {stu = stu} A B ⌉
+
+  _·_ : ∀ {Γ : Ctx} {s t u : Sort} {stu : ok3 s t u}
+    → {A : Γ ⊢ ⟪ s ⟫}
+    → {B : Γ , ⌈ A ⌉ ⊢ ⟪ t ⟫}
+    → (L : Γ ⊢ ⌈ Π_⇒_ {u = u} {stu = stu} A B ⌉)
+    → (M : Γ ⊢ ⌈ A ⌉)
+      ------------------------------------------
+    → Γ ⊢ ⌈ B ⌉ [ M ]
+
+data _⊆_ : Ctx → Ctx → Set
+
+_/_ : ∀ {Γ Δ : Ctx} → Γ ⊆ Δ → Tp Γ → Tp Δ
+
+_/∋_ : ∀ {Γ Δ : Ctx} {A : Tp Γ} → (θ : Γ ⊆ Δ) → Γ ∋ A → Δ ∋ θ / A
+
+_/⊢_ : ∀ {Γ Δ : Ctx} {A : Tp Γ} → (θ : Γ ⊆ Δ) → Γ ⊢ A → Δ ⊢ θ / A
+
+data _⊆_ where
+
+  ∅ :
+      -----
+      ∅ ⊆ ∅
+
+  W : ∀ {Γ Δ : Ctx} {A : Tp Δ}
+    → Γ ⊆ Δ
+      ---------
+    → Γ ⊆ Δ , A
+
+  S : ∀ {Γ Δ : Ctx} {A : Tp Γ}
+    → (θ : Γ ⊆ Δ)
+      -----------------
+    → Γ , A ⊆ Δ , θ / A
+
+∅ / A = A
+W θ / A = {!!}
+S θ / A = {!!}
+
+∅ /∋ x = x
+W θ /∋ x = {!S x!}
+S θ /∋ x = {!!}
+
+θ /⊢ A = {!!} 
+
+_[_]  =  {!!}
+
+_⟨_⟩  =  {!!}
+
+data _⟶_ where
+
+data _=β_ where
+
+
+
+\end{code}
+
diff --git a/src/plta/Lambda.lagda b/src/plta/Lambda.lagda
index 647bb933..bf136bc1 100644
--- a/src/plta/Lambda.lagda
+++ b/src/plta/Lambda.lagda
@@ -72,7 +72,7 @@ Three are for the naturals:
 
   * Zero, `` `zero ``
   * Successor, `` `suc ``
-  * Case, `` `case L [zero⇒ M |suc x⇒ N ] ``
+  * Case, `` `case L [zero⇒ M |suc x ⇒ N ] ``
 
 And one is for recursion:
 
diff --git a/src/plta/LambdaProp.lagda b/src/plta/LambdaProp.lagda
index 2662484d..cd20be8f 100644
--- a/src/plta/LambdaProp.lagda
+++ b/src/plta/LambdaProp.lagda
@@ -378,7 +378,7 @@ data Normalise (M : Term) : Set where
     → Normalise M
 
 normalise : ∀ {M A}
-  → ℕ
+  → Gas
   → ∅ ⊢ M ⦂ A
     -----------
   → Normalise M